Battery Watt-Hour (Wh) Calculator
モバイルバッテリーの多くはmAh表記ですが、航空会社の制限基準はワット時 (Wh) です。100Wh以下は機内持込自由、100〜160Whは航空会社の事前承認が必要です。
🔋 Battery watt-hour calculator
Power banks show mAh, airlines limit Wh. Under 100 Wh flies free in carry-on; 100–160 Wh needs airline approval.
よくある質問 (FAQ)
Frequently asked questions
How do you calculate Watt-hours (Wh) from mAh and Volts?
Formula: (mAh × V) ÷ 1,000 = Wh. For example, a 20,000 mAh power bank at 3.7V nominal is (20,000 × 3.7) ÷ 1,000 = 74 Wh.
What is the maximum battery size allowed on passenger planes?
Up to 100 Wh is freely permitted in carry-on bags. 100 Wh to 160 Wh requires airline approval (limit 2 spares). Over 160 Wh is strictly prohibited on passenger flights.